EXISTENCE OF GLOBAL ATTRACTORS FOR A NONLINEAR EVOLUTION EQUATION IN SOBOLEV SPACE Hk

In this paper we prove that the initial-boundary value problem for the nonlinear evolution equation ut = △u ＋ λu - u^3 possesses a global attractor in Sobolev space H^k for all k≥0, which attracts any bounded domain of H^k（Ω） in the H^k-norm. This result is established by using an iteration technique and regularity estimates for linear semigroup of operator, which extends the classical result from the case k ∈ [0, 1] to the case k∈ [0, ∞）.     

ON A HYPER HILBERT TRANSFORM＊＊＊＊

The authors define the directional hyper Hilbert transform and give ita mixed norm estimate. The similar conclusions for the directional fractional integral of one dimension are also obtained in this paper. As an application of the above results, the authors give the Lp-boundedness for a class of the hyper singular integrals and the fractional integrals with variable kernel. Moreover, as another application of the above results, the authors prove the dimension free estimate for the hyper Riesz transform. This is an extension of the related result obtained by Stein.     

CONVERGENCE OF CASCADE ALGORITHMS AND SMOOTHNESS OF REFINABLE DISTRIBUTIONS

In this paper, the author at first develops a method to study convergence of the cascade algorithm in a Banach space without stable assumption on the initial (see Theorem 2.1), and then applies the previous result on the convergence to characterizing compactly supported refinable distributions in fractional Sobolev spaces and Holder continuous spaces (see Theorems 3.1, 3.3, and 3.4). Finally the author applies the above characterization to choosing appropriate initial to guarantee the convergence of the cascade algorithm (see Theorem 4.2).     

优化Sobolev体及其仿射性质

Sobolev不等式是联系分析和几何的基础不等式之一,而优化Sobolev体是优化Sobolev范数的临界几何核.首先,证明优化Sobolev体的一些仿射性质.然后,运用Barthe的优化迁移方法研究了凸体的特征函数和多胞形仿射函数的优化Sobolev体.     

目标流形为Heisenberg群能量极小映射的逆Poincardé不等式

研究目标流形为Heisenberg群能量极小映射的性质,得到关于能量极小映射的逆Poincaré不等式.     

广义周期Besov类在周期Sobolev空间中的宽度

本文给出了一种广义周期Besov类在周期Sobolev空间中的n-宽度的弱渐近估计。     

带Carathodory函数的积分微分方程周期边值问题

本文研究带Caratheodory函数的非线性Volterra型积分微分方程周期边值问题．对于下解α与上解β的两种情形：或，解的存在性和建立极解的单调迭代法均被讨论．     

度量空间上Haj(l)asz-sobolev空间的新特征刻画

引进了包括分形和度量空间在内的齐型空间上的分数次Sobolev空间.这些Sobolev空间包括著名的Hajlasz—Sobolev空间为其特例,并建立了它们的各种Sharp极大函数的特征刻画.作为就用,证明了分数次Sobolev空间与某些Lipschitz型空间是一致的.此外,还给出了一些嵌入定理.